ice and snow accretion over the ukraine khomenko inna, odessa state environmental university,...

Ice and snow Ice and snow accretionaccretion

over the Ukraineover the Ukraine Khomenko Inna,Khomenko Inna,Odessa State Environmental University, UkraineOdessa State Environmental University, Ukraine

12th EMS12th EMS Annual Meeting & 9th European Conference on Applied ClimatologyAnnual Meeting & 9th European Conference on Applied Climatology

10 – 14 September 201210 – 14 September 2012

Łódź, PolandŁódź, Poland

Atmospheric icing is divided into

(1) precipitation icing

- glaze;

- wet snow;

- frozen wet snow;

(2) in-cloud icing

- hard rime;

- soft rime.

In order to study conditions of atmospheric icing near the surface such as glaze, soft and hard rime, snow accretion, the data for 185 stations of Ukraine are used for period of 2002-2009.

Database contains temperature, wind speed and wind direction in the beginning of icing accretion and at the moment that the accretion reached maximum in the size.

The database includes 18408 events.

Location of the cites in the Ukraine,for which the ice formation conditions are studied

Averaged number of icing days

For the landlocked mountainous terrainsuch as the Donetsk ridge,

the Crimean Mountains andthe Carpathians

the highest frequency of icing is reported (over 45 days per year).

Frequency distribution of atmospheric icing over the Ukraine

Frequency (%) of different types of icing accretion by month

1330 m

Frequency (%) of different icing accretion types by day time

Duration frequency (%) of different types of atmospheric icing

The highest duration of atmospheric icing is obtained for the Donetsk ridge.

Accumulated frequency (%) of different icing typesby mass of accretion

Maximum weight of accreted ice is reported for the Plai Mountain for all typeof atmosphere icing except wet snow.

Maximum wet snow accretion is observed in the Zaporizhzhia station.

GLAZE

89%

51%

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surface

HARD RIME

86%

33%

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surface

SOFT RIME

70%

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surface

WET SNOW 71%

Frequency distribution of surface temperaturein the beginning of the atmospheric icing near the surface

Frequency distribution of wind directionin the beginning of atmospheric icing near the surface

The most number of hard and soft

rime cases are reported under

calm

(soft rime 46%, hard rime 22%).

Frequency distribution of wind directionin the beginning of atmospheric icing

near the surface for various parts of the Ukraine

The further steps:

1. to create new detailed classification of territory of the Ukraine, according to the atmospheric icing severity;

2. to use the obtained results for developing of probabilistic forecast of atmospheric icing over Ukraine.